Circuit breaker combined with a visual indicator



0d. 2 2, 1963 w. M. CINIBULK 3,1

, CIRCUIT BREAKER COMBINED WITH A VISUAL INDICATOR Filed Jan; 5, 1961 3 Sheets-Sheet 1 [1 h Z J 22 J 2/ Z6 a /7 3 2/4 a 77 11 Hiiilllllllllil" m"...Im...@Immunnnmn j 6 4 2 1" a /i 4 VENTOR.

Oct. 22, 1963 w. M. CINIBULK CIRCUIT BREAKER COMBINED WITH A VISUAL INDICATOR Filed Jan. 5, 1961 3 Sheets-Sheet 2 Oct. 22, 1963 w. M. CINIBULK 3,108,165

CIRCUIT BREAKER COMBINED WITH A VISUAL INDICATOR Filed Jan. 5, 1961 3 Sheets-Sheet 3 INVENTOR.

United States Patent CERCUKT Filed Jan. 5, 1961, Ser. No. 884,397 6 Claims. (Cl. 20 3-421) This invention relates to circuit breakers and, more particularly, the invention is directed to a circuit breaker combined with a mechanism for visually indicating whether the main contacts operated by the circuit breaker are in open or closed condition.

The invention has particular application to those types of industrial-electrical systems wherein each of a large number of similar circuits is individually protected. In such a system it is common to mount circuit breakers on a large panel board with the circuit breaker being horizontally or perpendicularly aligned although the particular orientation of the circuit breakers with respect to each other does not form any part of the present invention. When circuit breakers are mounted in such clusters, it is important for the tripped condition of any of the circuit breakers to be determined visually and quickly so that any failure of a particular circuit can rapidly be perceived and stepstaken to remedy the fault which gave rise to the failure.

The present invention has been applied to a circuit breaker of the type disclosed in Patent No. 2,385,727 although the invention is not necessarily restricted to applications involving the patented circuit breaker. The patented circuit breaker is of the type which has a push button projecting from one end thereof, the push button cooperating with a pivotal and slidable plate mounted within the circuit breaker casing. Pushing in and releasing of the push button will, depending upon the original condition of the breaker, either open or close the contacts. Current responsive means coupled with a latch mechanism effects automatic opening of the contacts when the protected circuit has a fault creating excess current through the circuit breaker.

It has been an objective of the invention to provide, in a circuit breaker of the type described above, an auxiliary switch operated by the push button, the switch being in circuit with a light bulb or other indicating means which will provide a rapid indication of the condition of the circuit breaker. I

It has been another objective of the invention to'provide a push button type circuit breaker in which the push button is formed in part by a translucent cover or cap, the cover surrounding a light bulb which forms part of an auxiliary circuit, the auxiliarycircuit being closed only when the main circuit breaker contacts are closed.

It has been still another objective of the invention to provide a circuit breaker having a spring biased push button and a cooperating operating plate engageable with the push button to retain the push button in depressed condition only when the circuit breaker contacts are engaged. The surface on the plate which engages the circuit breaker is inclined to the direction of movement of the push button so as to reduce the criticality of the time and position of engagement of the push button with the plate when the circuit breaker contacts are set to a closed position. The purpose of maintaining the push button in a depressed condition is to utilize the push button as an indicator of the fact that the main contacts are engaged.

These and other objectives of the invention will become more readily apparent from the following detailed description taken in conjunction with the accompanying drawings in which:

BJil-SJhS Patented Get. 22, 1963 FIG. 1 is an elevational view of the invention with the cover removed;

FIG. 2 is an elevational view of the invention showing the main contacts in closed condition;

FIG. 3 is a cross-sectional view taken along lines 3-3 of FIG. 2;

FIG. 4 is a perspective view of the circuit breaker operating elements;

FIG. 5 is a perspective view of the push button assembly;

FIG. 6 is a disassembled perspective view of the operating elements; and

FIGS. 7-10 are elevational views of the operating elements illustrating several stages of operation.

The principal operating elements for the circuit breaker of the present invention are housed in a casing 15, the casing having a body portion 16, a top end closure 17, and a cover plate 18 (FIG. 3). The circuit breaker is operated by a push button 19 which passes through the bore 2t) in a tubular projection 21 integral with the top end closure 17 of the casing. The tube 21 is threaded as at 22 to receive an internally threaded nut by which the circuit breaker is secured to the panel board.

The lower section of the push button indicated at 25 has certain surfaces and projections to be discussed in detail below which cooperate with the main circuit breaker operating elements. These elements include a generally vertical plate 27 having a slot 28 in the lower corner thereof, the slot cooperating with a pin 29 which is integral with the body portion 16 of the casing.

The plate 27 has a hole 31 in which a contactor 32 is pivotally mounted by means of a pin 33. The pin 33 has an extension 34 which slidably engages cover 18 to maintain the elements in proper transverse position. The contactor 32 has current responsive means integrally secured thereto. In the present embodiment, the current responsive means comprises a generally J-shaped bimetallic element 36 which may be riveted, welded or other- Wise secured to the contactor 32, a rivet 3'7 being shown in the drawing. The free end 38 of the bimetallic element is connected by means of a copper pigtail 39 to a load terminal ill which passes through the wall of the body portion 16 of the casing. A line terminal 41 also passes through the Wall of the casing and has a contact tip 42 at the inner end thereof, the contact tip cooperating with a movable contact tip 43 integral with one end of the contactor 32.

The other end 45 of the contactor 32 has a projection 46 which receives one end 47 of the main operating spring 48. The other end 49 of the main operating spring is seated in a recess 50 in the Wall of the body portion 16 of the casing.

As best shown in'FIGS. 4 and 6, the free end 38 of the bimetallic element 36 has a transversely projecting flange 55. The flange has a latch shoulder or surface 56 which is engagcable with a vertical latch surface 57 on the plate 27. The elements are in a latched condition when the shoulder 56 is in engagement with the vertical latch surface 57 on plate 2'7 as shown in FIG. 4-. The engagement of the latch surfaces holds the elements in this condition against the urging of spring 43 which tends to pivot the bimetallic element 36 with respect to the plate 2.7. The elements can become uniatched either by manual operation of the push button as described below or by a flexing of the free end 38 of the bimetallic element toward the cover plate 13 upon an overload current passing through the element. It should be understood that other commonly used current responsive means, such as magnetic devices could be substituted for or used with the bimetallic element 36.

The lower section of the push button has surfaces and projections which cooperate with the plate 27 and bimetal 36 to effect the proper sequence of operations of the elements with respect to each other. A V-shaped projection 69 on the lower portion 25 of the push button is engageable with a V-shaped recess 61 on the upper edge of the plate 27. When the circuit breaker is in the unlatched condition as shown' in FIG. 1, the projection 69 is engageable with the recess 61 upon depressing the push button in order to force the plate 27 downwardly.

The lower portion 25 of the pushbutton also has an inclined carnsurface 62 which is engageable with the edge of the flange 55 projecting transversely from the bimetallic element 36. When. the circuit breaker elements are in the latched condition as shown for example flange 55 transversely away from plate 27 and thereby to effect the disengagement of the shoulder 55 with the latch surface 57 on the plate 27.

The lower portion 25 of the push button has an inclined shoulder 65 which is engageable by an inclined surface 66 formed by a pawl 67 at the end of a finger 63 on the plate 27. When the elements are in the latched condition shown in FIGS. 4 and 9, the engagement of the inclined surface 66 with the inclined shoulder 65 maintains the push button in a partially depressed condition.

The lower portion 25 of the push button also has a projection 7 :which is engageable with a movable auxiliary contact which may be the leaf spring contact 71 fixed at one end 72 to the body portion 16 of the circuit breaker casing. The other end 73 of the leaf spring contact is engageable with a fixed auxiliary contact 74 fixed to the wall of the casing. When the push button is held in a partly depressed condition as shown in FIGS. 4 and 9, the projection 76 bears against the leaf spring contact 71 to bring it into engagement with the fixed contact 74.

The auxiliary contacts 71 and 74 control a circuit to a light bulb 75 having a bayonet type mounting in a socket 76 The socket;76 is mounted to the body portion 16 of the casing by a metallic support 77 which is secured by a rivet 73 to the body portion 16 of the casing. The

rivet 78 also secures the end 72 of the leaf spring contact 71 and thereby provides an electrical connection between'the leaf spring contact and the support 77. As best shown in FIG. 3, the support 77 is secured to the centenpost 79 which makes electrical contact with a light bulb central terminal 8% by means or" a compression spring 81. Insulating means indicated at 82 maintains the central post 79 electrically isolated from the socket 7d; The socket 76 by means of wire 83 to a terminal 84 and the auxiliary contact 74 is connected by means of an electrical wire 85 to a terminal 86, the wires 83 and 85 being shown in hidden lines in FIG. 2. The terminals 84 and 86 will, when the breaker "is in use, be connected to a voltage source not shown.

The push button 19 is terminated in a translucent cap 87 shown in FIGS. 2 and so that when the light bulb 75 is energized, its radiation will be readily visible through the cap 87. 1

Operation The operation of the inventioncan best be understood by reference to FIGS. 7 to 10. Let it be assumed that the circuit breaker is in the condition shown in FIG. 7, that is, that the circuit breaker has been tripped and has not been reset. When the push button is depressed, the projection oil on the push button will engage the recess 61 on the plate 27 and drive the plate downwardly. In moving downwardly, the plate carries with it the assembly of contactor 32 and bimetal 36, the assembly being pivoted to the plate 27 by the pin indicated at 34.

The contactor 32 moves downwardly until it strikes the abutment 90 which is integral with the body portion 16 of the casing. Thereafter, continued downward movement of the plate 27 causes the contactor 32 to pivot counterclockwise as shown in FIG. 7. counterclockwise movement is continued until the latch shoulder 56 on the bimetal as snaps into engagement with the latch surface 57 on the plate 27. This latching occurs just short of the lowermost extremity of the inward stroke of the push button.

When the downward stroke of the push button has been completed, the push button is released. The contactor and bimetallic element assembly is oriented with respect to the plate 27 as shown in FIG. 9. The spring 48 holds the plate carrying with it its contactor 32 and bimetallic element 36 upwardly against the projection 60 on the push button as the push button is raised to the position shown in FIG. 9. FIG. 9 is illustrative of the intermediate stage at the instant that the contact tip 43 on the contactor 32 engages the fixed contact 42. Engagement of the contactor with the fixed contact 4-2 prevents further upward movement of the plate 27. Accordingly, continued upward movement of the push button withdraws the projection so from the recess st in the plate 27.

At this instant, the spring 48 causes the plate 27 to pivot clockwise thereby bringing the inclined surface 66 on finger 68 into engagement with the inclined shoulder 65 on the push button. The engagement of plate surface 66 with the inclined shoulder 65 prevents further upward movement of push button. The latched condi tion is thus illustrated in FIG. 9 in which it can be seen that the push button is slightly depressed. The extent of the depression of the push button is sufficient to maintain the projection 70 on the push button in engagement with the leaf spring contact 71. Thus by the simple depressing and releasing of the push button, the main contacts have been closed and the auxiliary contacts have been closed causing the illumination of the light bulb located within the push button.

. it should be noted that because of the inclined surface 66 on the finger 63 of plate 27, there is no criticality of the position of the push button to effect latching of the surface 66 with inclined shoulder 65. Rather, a range of positions of the push button is permitted within which satisfactory operation of the circuit breaker will occur. This range is sufiicient for all speeds of releasing the push button.

Opening of the main contacts 42 and 43 may be effected by one of two ways. First, upon overload of the circuit breaker the bimetallic element 36 flexes to the extent that the latch shoulder 56 moves out of engagement with the latch surface 57 on the plate 27. Second, the push button 19 may be depressed to the extent that the cam surface 62 moves into engagement with the edge of the flange 55 on bimetallic element 36 to force the latch shoulder out of engagement with the surface 57 on plate 27.

In either event, the disengagement of the latched surfaces $5 and 57 releases the contactor to pivot in a clockwise direction. As the contactor pivots in a clockwise direction, the contact tip 43 is swung away from the fixed contact 42 to bring the contactor to the position shown in FIG. 8. r

When the contactor becomes unlatched from the plate 27, the two members no longer move as a single unit. The spring 45 applies an upwardly directed force on the contactor 32. by means of the pins 33 and 34 to the plate 27, the point of application of the force being at the hole 31 in the to be repeated.

I claim: 1.'In a circuit breaker having a casing, a push button slidably mounted in the top of said casing, spring means The upwardly directed force is transmitted vertical position when said main contacts are open, and a pivoted position when said main'contacts are closed, the improvement comprising: a vertically projecting finger on said plate and having an inclined downwardly facing latch surface, a shoulder on said push button engageable with said latch surface only when said plate is in pivoted position to maintain said push button in a depressed position, an auxiliary contact fixed on a wall of said casing, a leaf spring contact fixed at one end to said casing and being engageable at the other end with said fixed auxiliary contact, a projection on said push button, said leaf spring lying in the path of said projection to force said leaf spring to engage said auxiliary contact only when said push button is in a depressed position, a light bulb in said push button, a translucent cover for said push button surrounding said'bulb, and circuit means for connecting said light bulb in series with said auxiliary contacts and a voltage source.

2. In a circuit breaker having a casing a push button slidably mounted in the top of said casing, spring means normally urging said push button outwardly, main contacts within said casing, and a pivotally mounted operating plate controlling said main contacts, said plate having a first position when said main contacts are open, and a second position when said main cont-acts are closed, the improvement comprising: a latch surface on said plate, a shoulder on said push button engageable with said latch surface only when said plate is in said second position to maintain said push button in a depressed position, an auxiliary contact fixed on a wall of said casing, movable auxiliary contact means mounted in said casing and being engageable with said fixed auxiliary contact, said movable contact means lying in the path of said push button, means on said pushbutton to force said movable contact means to engage said auxiliary contact only when said push button is in a depressed position, a light bulb in said push button, a translucent cover for said push button surrounding said bulb, and circuit means for connecting said light bulb in series with said auxiliary contacts and a voltage source.

3. In a circuit breaker having a casing, a push button slidably mounted in the top of said casing spring means normally urging said push button outwardly, main contacts within said casing, operating means located in said casing for said main contacts, said operating means being controlled by said push button, the improvement comprising: a contact operating projection on said push button, means to maintain said push button in a depressed position only when said main contacts are closed, an auxiliary contact fixed on a wall of said casing, a movable auxiliary contact means mounted in said casing and being engageable with said fixed auxiliary contact, said movable contact means lying in the path of said projection to force said movable contact means to engage said auxiliary contact only when said push button is in a depressed position, a light bulb in said push button, a translucent cover for said push button surrounding said bulb, and circuit means for connecting said light bulb in series with said auxiliary contacts and a voltage source.

4. In a circuit breaker comprising a casing, a push button slidably mounted in an aperture in the top of said casing, spring means normally urging said push button outwardly, an operating plate lying in a vertical plane in said casing, a pin integral with said casing projecting through a vertical slot in said plate, a contact fixed in said casing, a contactor pivotally mounted on said plate and having a contact tip engageable with said fixed contact, an operating spring normally urging said contactor to pivot in a direction to move its contact tip downwardly away from said fixed contact, a current responsive element fixed at one end to said contactor and having a latch surface at the other end, a latch surface on said plate cooperating with said latch surface on said element to block spring urged pivotal movement of said element, said contact tip being in engagement with said fixed contact when said latch surfaces are engaged, the improvement comp-rising: an auxiliary contact fixed on a wall of said casing, a leaf spring contact fixed at one end to said casing and being engageable at the other end thereof with said fixed auxiliary contact, a projection on said push button, said leaf spring lying in the path of said projection to force said leaf spring to engage said aux-iliary contact only when said push button is in a depressed position, a light bulb in said push button, a translucent covering for said push button surrounding said bulb, circuit means for connecting said light bulb in series with said auxiliary contacts and a voltage source, an inclined latch surface on said plate, and a cooper-ating latch surface on said push button, said latch surfaces cooperating to hold said push button in a depressed position only when plate and element latch surfaces are latched.

5. In a circuit breaker comprising a casing, a push button slidably mounted in an aperture in the top of said casing, spring means normally urging said push button outwardly, an operating plate lying in a vertical plane in said casing, a pin integral with said casing pno-jecting through a vertical slot in said plate, a contact fixed in said casing, a contactor pivotally mounted on said plate and having a contact tip engageable with said fixed contact, an operating spring normally urging said contactor to pivot in a direction to move its contact tip downwardly away from said fixed contact, a current responsive element fixed at one end to said contactor and having a latch surface at the other end, a latch surface on said plate cooperating with said latch surface on said element to block spring urged pivotal movement of said element, said contact tip being in engagement with said fixed contact when said latch surfaces are engaged, and means for maintaining said push button in a depressed position when said contacts are closed, the improvement comprising: an auxiliary contact fixed on a wall of said casing, a leaf spring contact fixed at one end to said casing and being engageable at the other end thereof with said fixed auxiliary contact, a projection on said push button, said leaf spring lying in the path of said projection to force said leaf spring to engage said auxiliary contact only when said push button is in a depressed position, a light bulb in said push button, a translucent covering for said push button surrounding said bulb, circuit means for connecting said light bulb in series with said auxiliary contacts and ayoltage source.

6. In a circuit breaker comprising a casing, a push button slidably mounted in an aperture in the top of said casing, spring means normally urging said push button outwardly, an operating plate lying in a vertical plane in said casing, a pin integral with said casing projecting through a vertical slot in said plate, a contact fixed in said casing, a contact-or p-ivotally mounted on said plate and having a contact tip engageable with said fixed contact, an operating spring normally urging said contactor to pivot in a direction to move its contact tip downwardly away from said fixed contact, a current responsive element fixed at one end to said contactor and having a latch sun-face at the other end, a latch surface on said plate coopenating with said latch surface on said element to block spring urged pivotal movement of said element, said contact tip being in engagement with said fixed contactwhen said latch surfaces are engaged, and means for maintaining said push button in a depressed position when said contacts are closed, the improvement comprising: an auxiliary contact fixed on a wall of said casing, movable auxiliary contact means mounted in said casing and being engageable by said push button, said movable contact means lying in the path of said push References Cited in the file of this patent UNITED STATES PATENTS Winning Apr. 7, Platz Sept. 25, 'Davis Aug. 7, Ellenberger Feb. 25, MeMains Aug. 15, 

3. IN A CIRCUIT BREAKER HAVING A CASING, A PUSH BUTTON SLIDABLY MOUNTED IN THE TOP OF SAID CASING SPRING MEANS NORMALLY URGING SAID PUSH BUTTON OUTWARDLY, MAIN CONTACT WITHIN SAID CASING, OPERATING MEANS LOCATED IN SAID CASING FOR SAID MAIN CONTACTS, SAID OPERATING MEANS BEING CONTROLLED BY SAID PUSH BUTTON, THE IMPROVEMENT COMPRISING: A CONTACT OPERATING PROJECTION ON SAID PUSH BUTTON, MEANS TO MAINTAIN SAID PUSH BUTTON IN A DEPRESSED POSITION ONLY WHEN SAID MAIN CONTACTS ARE CLOSED, AN AUXILIARY CONTACT FIXED ON A WALL OF SAID CASING, A MOVABLE AUXILIARY CONTACT MEANS MOUNTED IN SAID CASING AND BEING ENGAGEABLE WITH SAID FIXED AUXILIARY CONTACT, SAID MOVABLE CONTACT MEANS LYING IN THE PATH OF SAID PROJECTION TO FORCE SAID MOVABLE CONTACT MEANS TO ENGAGE SAID AUXILIARY CONTACT ONLY WHEN SAID PUSH BUTTON IS IN A DEPRESSED POSI- 